Beyerdynamic MA 212 Stereo Amplifier User Manual


 
english
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4. Connections
4.1 Microphone inputs
On the rear there are two XLR-connections (16). The microphone connection is
balanced (pin 2+3 signal AF, pin 1 ground shield). For each input the input gain
(1 - 100 mV) can be adjusted internally on the printed circuit board (refer to chapter
“9. Printed circuit board”). The input volume is adjusted on the front using the
volume control (1). The microphone inputs 1 and 2 can be switched to priority (refer
to chapter “4.1.1 Priority switching”).
Caution:
All balanced microphone inputs have an adjustable phantom power from 0
to +24 V. If you connect microphones or wireless microphone receivers with
unbalanced outputs you have to insert a coupling capacitor or the mixer
amplifier will be seriously damaged.
4.1.1 Priority switching
The priority of the privileged microphone inputs is voice-controlled (ducking
function). The unit is delivered with this function being deactivated. If the ducking
function is desired, the bridge resistors on the printed circuit board have to be sol-
dered (refer to chapter “9. Top view of the printed circuit board”). The programme
fades out when someone is speaking into the microphone. Possible microphones are
a handheld mic or a desktop microphone unit.
Microphone 1 has priority over microphone 2. Both microphones fade out the uni-
versal input and the auxiliary input. The fade-out can be adjusted from 0 to -40 dB
on the printed circuit board (refer to chapter “9. Top view of the printed circuit
board”).
4.2 Universal input
The universal input is a 1/4" jack for the connection of a microphone (unbal-
anced) or a low-level line input (RCA). The input gain for the microphone
(3 mV) and the low-level input (250 mV/-10 dB) is fixed.
4.3 Auxiliary input
On the rear of the mixer amplifier there is one adjustable RCA (phono) connec-
tion for input and one RCA (phono) connection for the record output. The connec-
tions are unbalanced and suitable for stereo carriers (L + R are internally switched
together via an impedance matrix). The master signal from the auxiliary and micro-
phone inputs is available at the record output; independent of the equalisation (bass
and treble) (4) and the master volume control (5).